Broccoli · Edmonton, Alberta, Canada
When to plant broccoli in Edmonton
Main outdoor window
29 Apr - 20 May
The window this page is built around.
Timed from last spring frost
13 May
In Edmonton, on your chosen risk.
Ready to pick
28 Jun - 28 Jul
If you plant at the start of the window.
The average last frost. Half of all years are later than this.
Step by step in Edmonton
Each window is a range, not a single day. Earlier in the range buys you a longer season; later in it buys you a safer one.
Start indoors
25 Mar - 15 Apr
Seven weeks before your last frost, under cover or on a windowsill.
Plant out
29 Apr - 20 May
Two weeks before your last frost.
Harvest
28 Jun - 28 Jul
Broccoli through the year
Against the frost risk in Edmonton
Why these dates
Aim to have heads maturing before summer heat or after it. A midsummer maturity date produces small, loose, bitter heads no matter how well you grow the plant.
Transplants take -6C. Purple sprouting types are far hardier and are grown deliberately through winter for a spring crop.
Seed packets and extension guides express timing as weeks either side of the last spring frost, because that is the only reference point that travels. Broccoli are timed from 7 weeks before that frost for an indoor start, with planting out 2 weeks before it, and this page simply resolves those offsets against the frost date computed for Edmonton.
The median frost-free season here is 137 days, against 60 to 90 days to maturity for this crop counted from planting out. That margin is what decides whether a late sowing is worth attempting.
Also in Edmonton
Other vegetables to time
Growing broccoli in Edmonton
When should I plant broccoli in Edmonton?
Aim for 29 Apr - 20 May in an average year. If you would rather not gamble on the weather, wait until 8-29 May - by then frost has finished in nine years out of ten.
When will broccoli be ready to harvest in Edmonton?
Expect to start picking around 28 Jun - 28 Jul, based on 60 to 90 days to maturity from the planting date calculated for this location.
How much frost will broccoli tolerate?
Transplants take -6C. Purple sprouting types are far hardier and are grown deliberately through winter for a spring crop.